aboutsummaryrefslogtreecommitdiff
path: root/lib/mlibc/options/ansi/generic/complex/carg.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/mlibc/options/ansi/generic/complex/carg.c')
-rw-r--r--lib/mlibc/options/ansi/generic/complex/carg.c59
1 files changed, 59 insertions, 0 deletions
diff --git a/lib/mlibc/options/ansi/generic/complex/carg.c b/lib/mlibc/options/ansi/generic/complex/carg.c
new file mode 100644
index 0000000..0447420
--- /dev/null
+++ b/lib/mlibc/options/ansi/generic/complex/carg.c
@@ -0,0 +1,59 @@
+/* $NetBSD: carg.c,v 1.1 2007/08/20 16:01:31 drochner Exp $ */
+
+/*
+ * Written by Matthias Drochner <drochner@NetBSD.org>.
+ * Public domain.
+ *
+ * imported and modified include for newlib 2010/10/03
+ * Marco Atzeri <marco_atzeri@yahoo.it>
+ */
+
+/*
+FUNCTION
+ <<carg>>, <<cargf>>---argument (phase angle)
+
+INDEX
+ carg
+INDEX
+ cargf
+
+ANSI_SYNOPSIS
+ #include <complex.h>
+ double carg(double complex <[z]>);
+ float cargf(float complex <[z]>);
+
+
+DESCRIPTION
+ These functions compute the argument (also called phase angle)
+ of <[z]>, with a branch cut along the negative real axis.
+
+ <<cargf>> is identical to <<carg>>, except that it performs
+ its calculations on <<floats complex>>.
+
+RETURNS
+ @ifnottex
+ The carg functions return the value of the argument in the
+ interval [-pi, +pi]
+ @end ifnottex
+ @tex
+ The carg functions return the value of the argument in the
+ interval [$-\pi$, $+\pi$]
+ @end tex
+
+PORTABILITY
+ <<carg>> and <<cargf>> are ISO C99
+
+QUICKREF
+ <<carg>> and <<cargf>> are ISO C99
+
+*/
+
+#include <complex.h>
+#include <math.h>
+
+double
+carg(double complex z)
+{
+
+ return atan2( cimag(z) , creal(z) );
+}